As a new type of solid light sources, white light LEDs, with many advantages including high light efficiency, low energy consumption, long lifetime and no pollution and so on, have been widely applied in the field of illumination and display. At present, white light LEDs are mainly implemented by means of compound fluorescent powder with a single blue light/purple light chip. The solution is simple, easy and relatively cheap.
In the field of illumination, as an important indispensable component in the three primary colors of red, green and blue, the green fluorescent powder can be also matched with a blue light LED and red fluorescent powder to generate white lights in addition to the application in compensating the lack of green in “blue light LED+YAG:Ce3+”. It is important that the green fluorescent powder plays an extremely important role in improving the color rendering index of the white light LED. Moreover, during an implementation process of a liquid crystal backlight LED, a range of a color gamut of liquid crystal display is directly determined by a blue light chip, red fluorescent powder and green fluorescent powder. Therefore, the quality of green fluorescent powder has also become a key factor that influences the quality of liquid crystal display.
The emerging nitrogen/nitrogen oxide green fluorescent powder has attracted much attention since it came out, and its major component is a Sr—Al—Si—N—O compound activated by Eu ions or Ce ions, wherein the nitrogen/nitrogen oxide green fluorescent powder includes the following components: MSi2O2N2: Eu2+ (M=Ca, Sr, Ba), M3Si6O12N2:Eu2+ (M=Ca,Sr,Ba), Ca-α-Sialon and β-Sialon green fluorescent powder and so on.
At present, green fluorescent powder needs to be further researched to provide more alternatives for the application of green fluorescent powder, and then to adapt to the rapid development of white light LEDs.